OCEAN · DISSOLVED OXYGEN

Dissolved Oxygen

How much oxygen is dissolved in the surface water — a live global map of the gas every animal in the sea must breathe (mmol/m³). Bright where cold, well-mixed, productive seas hold the most (the Southern Ocean, the North Atlantic and Pacific); dark over warm tropical water and the great oxygen-minimum zones off Peru, off West Africa and in the Arabian Sea. Oxygen is the ocean’s vital sign: where it falls too low the water becomes a dead zone, and a warming ocean holds and mixes less of it. The open ocean has already lost roughly 2% of its oxygen since the mid-20th century. The “ocean losing its breath” climate signal — a biogeochemistry field no keyless raster on this canvas provides. Updated daily.